diff --git a/src/cmd/acid/proc.c b/src/cmd/acid/proc.c
index 2c286e1..6699634 100644
--- a/src/cmd/acid/proc.c
+++ b/src/cmd/acid/proc.c
@@ -30,7 +30,7 @@
 	correg = nil;
 
 	if(mapproc(xpid, cormap, &correg) < 0)
-		error("setproc %d: %r", pid);
+		error("setproc %d: %r", xpid);
 
 	/* XXX check text file here? */
 
@@ -165,6 +165,17 @@
 	s->v->set = 1;
 }
 
+static int
+installed(int pid)
+{
+	int i;
+
+	for(i=0; i<Maxproc; i++)
+		if(ptab[i].pid == pid)
+			return 1;
+	return 0;
+}
+
 void
 deinstall(int pid)
 {